Fallback from HEAD to GET for HttpUtils.resourceAvailable as well
When long messages are displayed to user, make them scrollable
Don't throw RuntimeException if can't get content length
Put overlay tracks option into production

IGV-1979
Catch exception when loading system proxy

Some users reported errors loading system proxy setting on CentOS. This may help
Only decode index file string if it's been provided
Fix bug where scatterplot hotkey was under ctrl+s, and showStatus was unavailable
Add ctrl+s hotkey, which sorts alignment tracks by previous sort

IGV-2062
Merge remote-tracking branch: upstream/master